Abstract: Three patterns of marine hydrocarbon source rocks are established based on previous researches on several prominent marine source rocks around the world. The organic geochemistry feature, paleoenvironmental and paleoceanic conditions are collected to constrain the factors of productivity, sources and preservations of the organic matter. The patterns are as fellows: ①delta -terrestrial sourced marine facies pattern; ②evaporated-ocean upwelling pattern; ③restricted sea-humid climate-pattern. Previous researches have shown that the Enping-Zhuhai formation (Eocene-Oligocene) in the deepwater area of the northern South China Sea was formed under a restricted Marine environment, with developed delta sedimentary system, sufficient supply of terrestrial organic matter. According to this reviews, we suggest that there is a great potential for exploration of the marine hydrocarbon source rocks in the deepwater area in the northern South China Sea.